Ezea hollis geiffith



-(No Model.) v I 2 Sheets-Shet 1.

E. H. GRIFFITH.

'MICROSGOPISTS TURN TABLE. No. 354,130. Patented 1360.14, 1886.

311mm, Qmmninr:

(No Model.) 2 Sheets-Sheet 2. B. H. GRIFFITH.

MIGROSGOIEISTS TURN TABLE.

Patented Dec; 14, 1886.

///fl/////////IIII flaw/awn NITE STATES ATENT Erica.

EZRA HOLLIS GRIFFITH, OF FAIRPORT, NEW YORK.

MICROSCOPISTS TURN-TABLE.

SPECIFICATION forming part of Letters Patent No. 354,130, dated December14, 1886.

Application filed April 8, 1686. Serial No. 198,289. (No model.)

New York, have invented a new and useful Improvement in Turn -TablesDesigned for Microscopists Use, which improvement is fully set forth inthe following specification, which I declare to be a full, clear, andexact description of my invent-ion,which will enable others skilled inthe art to which it pertains to make and use the same, rel'erencebeinghad to the accompanying drawings. 7

My invention relates to the class of turntables commonly designated ascentering turntables, in which, by appropriate mechanism, the glass slipon which objects are mounted by microscopists is, when placed on theturn-table for treatment, automatically brought to a certain definiteposition and held there during the subsequent manipulations of theoperator; and the object of my invention is to afford the means ofbringing the slips used for mounting objects automatically to a certaindefinite position, and also the means of varying at will the position ofthe slip on the turntable to make the same conform to the position itwould assume when placed upon different forms of turntable, and toenable the turn-table to be used as a component part of other mechanism.These objects I accomplish by means of the mechanism shown in the accompauying drawings, in which Figure 1 is a plan view of the top of theturn-table, holding a glass slip as in ordinary use. Fig. 2 is asectional view of the turntable on the line 00 y of Fig. 1, the viewbeing taken in the direction indicated by the arrow in Fig. 1. Fig. 3 isa plan view of the under side of the disk B; and Fig. 4C is a partialsectional view of Fig. 1 on the line 20 z of Fig. 1, viewed in the samedirection as Fig. 2. Fig. 5 is a plan view of the turn-table with lugsor feet attached; and Fig. 6 is a sectional view on the line a: y ofFig. 5, viewed in the same direction as Fig. 2.

Similar letters of reference indicate similar parts in all the figures.

A is a flat disk, of metal, forming the turntable top, and by means of ahollow stem underneath poised centrally upon a spindle in the usualmanner. Bisasmaller disk revolving in a central depression formed in A,and so fitted that its surface is fiush with that of disk A. O is asmall disk, also revolving in a recess in the upper surface of A,withits surface flush with that of disk A. The glass slip in use lies partlyupon all of these three disks A B O, as shown in Fig. 1. The disk B isactuated by a spring on its under side, which may be any form of springso adapted as to tend to rotate the disk B in the direction indicated bythe curved arrow on disk B in Fig. l for about one-quarter of arevolution.

In the drawings, Z is a flat spring rigidly attached at one end to theunder side of disk B, and with its free end bearing against a stud orpin, is, projecting from disk A, and so placed that when the disk B isrotated in a direction contrary to that shown by the arrow thespringlwill bend, as shown by dotted lines in Fig. 3 and also in Fig. l, andtend to return the disk B to its first position.

d d are two pins in the upper surface of disk B, near its edge, onopposite sides, and a little more than one inch apart, in order toeasily admit between them the glass slips used, which are of a uniformor standard size of one inch in width and three inchesiu length.

6 is a pin rigidly fixed in the suri'aceoi' disk A, a little less thanone and one-half inch from its center.

f is a pin threaded below and passing up through the disk A, near the pn e, and at a distance of exactly one and one half inch from the centerof disk A, which is also the center of revolution of the slip in use.The threaded part of pinf has sufificient bearing in disk A to allow itto be so far withdrawn that it will be wholly below the surface of diskA without being entirely removed. To facilitate the use of this pin, itis provided with a milled head, it, at its lower end.

9 is a pin rigidly fixed in the disk 0 near its edge, and his a stemcentrally affixed to the disk 0 and extending down through disk A, belowwhich it is provided with a suitable handle, j, for operating the disk0; but the disk 0 may be eccentrically pivoted on the surface of thetable A and the stem h and handle j be dispensed with.

m is the glass slip in use,placed in Fig. 1 in the position mostcommonly used.

n'is a short screw, holding disk B in place and forming a pivot ,uponwhich it rotates.

O are lugs or projections attached by any suitable means to theperipheryof disk A, equidistant from each other, and so formed as to projectabove its upper surface at their extremities slightly more than the pinsd, e,f, and g. The turn-table is operative and efficient without theselugs; but their weight adds to its momentum in revolution, and theyserveas feet when the turn-tableis reversed, as hereinafter described. 1

I P is a spindle set rigidly in a foot or support, g, which forms partof a hand-rest of the common form.

R is a hollow stem fitting the spindle P, and having at its lower end amilled collar, S, attached to it, by which the whole may be revolved byturning it with the fingers. The stem R may be solid with disk A, orseparately formed and rigidly attached thereto, in which case the screwa may be dispensed with, and disk B may beinserted within a countersunkrecess in A from below, and held in place by the enlarged top of stem R,screwed into the lower part of such recess, as shown in Fig. 6, andbearing the pin is.

The operation of my improved turn-table is as follows: The slip to beoperated upon is placed on the table between the pins d d, the slip-diskB and pins 02 d, when left to the action of spring Z, being in theposition shown by dotted lines. in Fig. 5. By turning back the diskagainst the action of the spring the slip is brought to a position inwhich it can be pushed past the pin 6 to the position shown by fulllines in Fig. 1, when it bears against pin f in its ordinary position,and the center of the slip m coincides with that of disk A, in whichposition it will be held by the pins d d and the action of the spring Z,which remains in the bent position shown by dotted lines in Fig. 1, thedisk 0 being sov turned that pin g will not bear against the slip m.

it is always desirable and often necessary to be able to decenter slipsupon a turn-table when in use, and for that purpose I have provided disk0 and pin 9, and by turning disk 0 by means of the handle j and stem hthe pin 9 is caused to press against the slip m and force it away fromthe position shown in Fig. 1, the spring Z giving way to permit thismovement. In case it is found necessary to decenter the slip m in thedirection of its length, the pin f is, by its milledhead t, underneaththe table, turned down below the surface of disk A, when the slip m mayvbe pushed over and past it.

By reversing the slip endwise any portion ordinarily used may be broughtover the center of revolution of the turn-table and operated upon. Thishas not heretofore been accomplished in any centering turn-tablewithoutthe use of supplementary wedges or blocks, which are very objectionablein use.

It is also desirable for many purposes to be able to remove theturn-table top with the slip in place from the spindle upon which it issupported. In my improved form of turntable this may readily be done,and the turntable so removed from its spindle may be placed top downwardupon any smooth surface without injury to the slip m in place upon it,or to any object, cover, or cement attached to the slip m, theprojection of the feet or lugs 0 above the surface of the turn-table toppreventing the slip m, or object or cement attached to it, from touchingthe surface'upon which the turntable is so placed. When thus removed andplaced face downward, the turntable top forms a suitable and convenientbase for the attachment of other apparatus used by microscopistssuch asdissecting-lenses, heating-plates, and many others-and may be used asthe foot or base of a microscope, the accessory apparatus used beingattached to the turn-table by means of the screw-thread W thereon, forwhich purpose the milled collar S may be removed; or the stem B may beprovided also with an internal screw-thread for the tion, with the tableA, of the removable hearing f and the decentering-disk O, substantiallyas described. p

4. The turntable A, with fixed bearing 0, and removable bearing f,having a central rotating disk,-.B, provided with fixed bearingsd d, andactuated by a spring to hold the slide in use against the bearing e,substantially as described. 1

ICO

5. In a turn-table, the decentering-disk C,ec-

use, subdecentering-disk 0, pin 9, and handle h, for projecting abovethe surface of the table, and I0 operating the disk 0, substantially asshown the hollow stem R, provided with a screwand described. thread forthe attachment thereto of accessory 8. The combination of the table A,disk B, apparatus, substantially as described.

5 pins d, e, and f, and lugs O, substantially as EZRA HOLLIS GRIFFITH.

described.

9. In a turn-table, the combination, with XVitnesses: the table A,having on its surface bearings for SAMUEL W. DENNIS, clasping andholding a slip, of the lugs O, HOLLAND SMITH.

